Material Properties

M Barnwell Services offers an unrivalled range of materials properties suitable for every fluid sealing application and industry. Our Quality and Purchasing teams work hand in hand to source, develop, check and approve a vast range of Materials to meet the increasing demands of today’s engineering applications.

M Barnwell Services are proud to state that we are the UK’s largest independent stockist and distributor of all type of fluid sealing products.

The below information had been derived from numerous sources and the ratings are therefore intended as a guide only. Users must test under their own operating conditions to determine suitability of any compound in a particular temperature and/or application.

Features & Resistance: Excellent resistance to gasoline, alcohol, fuel additives, acids, hydrocarbons, water, oils, oxidation, ageing, ozone, radiation, heat, weather. Very low gas permeability, excellent for vacuum applications, self-extinguishing, dynamic, compression set resistance, tensile strength, superior swell in high octane and oxygenated fuels. Good abrasion resistance and chemical resistance. Moderate tear resistance and water steam resistance. In addition to the standard FKM/FPM materials, a number of special compounds with different compositions of polymer chains and varying fluoro contents (65% to 71%) are developed for special applications.

Key Uses: where high resistance is needed to chemical and high temperature attacks, aircrafts, cars, and various mechanical devices that require maximum resistance to high temperatures, automotive fuel handling, general industrial seals and gaskets, food applications

Features & Resistance: HG hard fabric materials are produced from various fabric/resin combination, such as:

Synthetic fibre fabric + phenolic resin

Cotton fabric + phenolic resin or

Polyester fabric + polyester resin.

With a selection of the optimal material combinations (fabric/resin), a long product life, high restoring force, low friction (dry-running characteristics exist) and a very high contact pressure (load capacity) can be achieved.

Standard material displays no moisture expansion in water; or measurable absorption of water.

Features & Resistance: HNBR is also known as Saturated Nitrile (HSN). It is acquired by initiating Hydrogen into the Nitrile in order to saturate the hydrocarbon sequences in the elastomer. Excellent physical strength, abrasion resistance, compression set and impact resistance. Good gas permeability, resilience and steam resistance. Better wear and extrusion resistance than Nitrile (NBR), good chemical compatibility.

Key Uses: All oil applications, including exposure to oil additives and detergents, anti-oxidants, and anti-wear agents. Exposure to oil soured with metal sludge. Seals for oil well applications and automotive fuel handling systems, seals for general industrial use, food applications

Features & Resistance: Impregnated rubber materials. Cotton or synthetic fibre fabric can be used as the basis for rubber fabric materials. The standard material for hydraulic seals is cotton fabric. In addition to the standard material, a whole range of other fabric types and almost all elastomers for impregnation are available. For the production of hydraulic seals, the fabric is impregnated with an NBR elastomer solvent. Subsequently, appropriate dimensions are cut out of the impregnated cloth and rolled for further processing and then vulcanised in a vulcanisation press, under the influence of temperature and time, to produce hydraulic seals. Hydraulic seals are either produced totally of rubber fabric material or segments of the elastomer part are reinforced with fabric, e.g. the running surface or the side facing away from the pressure, to achieve better protection from gap extrusion. The so called multi component seal can be produced by vulcanising pure elastomer onto the seal.

Advantages: High wear resistance, very good friction, and sliding properties, good low-temperature resistance, and high-pressure load and extrusion resistance, very dimensionally stable and have low moisture expansion tendency in hydraulic media, very robust material

Key Uses: Particularly well suited for rough application conditions such as in mobile hydraulics or other heavy-duty applications

Features & Resistance: High resilience and tensile strength, able to absorb vibration. High resistance to abrasion and tear, and excellent adhesion to metals. Good resistance to alcohols and organic acids, moderate resistance to aldehydes.

Features & Resistance: Similar properties to Natural Rubber (NR). Excellent abrasion and water resistance, good friction surface. Good bonding and wear characteristics, heat ageing properties and strength. Good compression set and gas permeability. Good resistance to brake fluids and water.

Features & Resistance: Excellent resistance to abrasion and extrusion. Good gas tightness, high level of tolerance to wide range of gases including oxygen, nitrogen, and all synthetic hydrocarbons.
No brittleness as consequence of exposure to ozone or oxygen, low swelling in mineral oil, hydraulic media and lubricating greases. Generally good chemical resistance and superb dynamic behaviour.

Features & Resistance: Excellent tear, impact and abrasion resistance, good gas permeability, steam resistance and compression set. Can be used with petroleum oils and water. Excellent oil and solvent resistance, high tensile strength and good physical properties at high temperatures. Very good resistance to oils and greases, high resistance to wear and abrasion.